<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<body>
<div id="box">
<div class="top">
    <select  id="month"></select>
</div>
</div>
</body>
<script>
    var listYear= document.getElementById("year");
    for (var i=1900;i<2051;i++){
        /*生成一个元素节点*/
        var year = document.createElement("option");
        year.innerHTML=i;
        year.value=i;
      /*  往listyear节点内部子集后面加子节点*/
        listYear.appendChild();
    }
</script>
</html>